The 757s in Shannon do make money to be fair. SNN-BOS wouldn't be getting upgraded to a 767 if it wasn't making money, and SNN-LHR feeds BA so I don't see why that would go if IAG took over. Eventually the 757s will be replaced by 321 neos. However given IAG's policy of focusing on their hubs, would there be any based in SNN in the long run? If not one of DL/AA would probably go year round.
I wasn't able to decide if IAG would be good or bad for EI, going through all the positives and negatives. I now think it will be a huge opportunity missed in the medium to long term if IAG don't take over. Once again parish pump politics is threatening to screw this airline, and the Irish aviation sector as a whole.